The councils, a partnership made up of Bath and North East Somerset, Bristol City, North Somerset and South Gloucestershire councils, will save £44m over the next five years and divert about 75% of biodegradable waste from landfill.

The deal, signed last week, will see residual or ‘black bag waste’ treated through a bio-stabilisation process to create compost for use in land restoration.

The process, awarded to New Earth Solutions, will see black bags put into a macerator to sift out the biodegradable waste.

The leftovers, about 25% of the total waste, are a mixture of plastic, paper, metal and organic material, which is taken away to be recycled.

The leftover organic waste is then heated, composted stored for four weeks inside and four weeks outside while being sifted.

The end result is a soil restoration product with a high level of nitrogen and phosphorus allowing it to be used as a soil improver.

As the original waste comes from mixed black bag waste small particles of non-biodegradable waste may remain in it meaning it is not suitable for domestic applications but is best used as a sub soil in commercial land reclamation projects.

The contract requires New Earth Solutions to accept 120,000 tonnes a year of waste from the West of England councils from April/May 2011 onwards.

Currently residents and businesses in the West of England generate about 1.5m tonnes of rubbish every year

Chairman of the joint waste committee, councillor Carl Francis-Pester, said: “This is an important milestone for the partnership.

“By working together we have been able to secure an excellent arrangement with New Earth Solutions that will greatly reduce the amount of waste we send to landfill and will save the councils millions of pounds.”

Luke Walsh

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